When you don’t have enough resources, prioritization becomes even more important. You don’t have the luxury to execute every single great idea that you have. You need to pick and choose, and the life of your company depends on choosing wisely.

Why is it that so many startups work so hard on the wrong stuff? By “the wrong stuff” I mean, of course, stuff that doesn’t move a key metric — projects that don’t convert people into new users or increase revenue or drive retention. And it’s especially problematic for new startups, since they are often missing really important features that would drive all those key metrics.

It’s as if they had a car without any brakes, and they’re worried about building the perfect cupholder.

For some reason, when you’re in the middle of choosing features for your product, it can be really hard to distinguish between brakes and cupholders. How do you do it?

You need to start by asking (and answering) two simple questions:

What problem is this solving?

How important is this problem in relation to the other problems I have to solve?

To accurately answer these questions, it helps to be able to identify some things that frequently get worked on that just don’t have that big of a return. So, what does a cupholder project look like? It often looks like:

Visual Design — Visual design can be incredibly important, but nine times out of ten, it’s a cupholder. Obviously colors, fonts, and layout can affect things like conversion, but it’s typically an optimization of conversion rather than a conversion driver.For example, the fact that you allow users to buy things on your website at all has a much bigger impact on revenue than the color of the buy button. Maybe that’s an extreme example, but I’ve seen too many companies spending time quibbling over the visual design of incredibly important features, which just ends up delaying the release of these features.

Go ahead. Make your site pretty. Some of that visual improvement may even contribute to key metrics. But every time you put off releasing a feature in order to make sure that you’ve got exactly the right gradient, ask yourself, “Am I redesigning a cupholder here, or am I turbocharging the engine?”

Retention Features — Retention is a super important metric. You should absolutely think about retaining your users – once you have users.

Far too many people start worrying about having great retention features long before they have any users to retain. Having 100% retention is a wonderful thing, but if your acquisition and activation metrics are too low, you could find yourself retaining one really happy user until you go out of business.

Before you spend a lot of time working on rewards for super users, ask yourself if you’re ready for that yet. Remember, great cupholder design can make people who already own the car incredibly happy, but you’ve got to get them to buy it first, and nobody ever bought a junker for the cupholders.

Animations — I am not anti-animation. In fact, sometimes a great animation or other similar detail in a design can make a feature great. Sometimes a well designed animation can reduce confusion and make a feature easy to use.

The problem is, you have to figure out if the animation you’re adding is going to make your feature significantly more usable or just a little cooler.

As a general rule, if you have to choose between usable and cool, choose usable first. I’m not saying you shouldn’t try to make your product cool. You absolutely should. But animations can take a disproportionate amount of time and resources to get right, and unless they’re adding something really significant to your interface, you may be better served leaving them until later.

“But wait,” a legion of designers is screaming, “we shouldn’t have to choose between usable and cool! Apple doesn’t choose between usable and cool! They just release perfect products!”

That’s nice. When you’ve got more money than most first world governments, you’ve got fewer resource constraints than startups typically do. Startups make the usable/cool trade off every day, and I’ve looked at enough metrics to know that a lot of cool but unusable products get used exactly once and then immediately abandoned because they’re too confusing.

Note: this may seem to contradict my point about attracting users first and then worrying about retention, but I’d like to point out that there’s a significant difference between solving long term retention problems and confusing new users so badly that they never come back.

Before you spend a lot of time making your animation work seamlessly in every browser, ask yourself if the return you’re getting is really worth the effort, or if you’re just building an animated cupholder.

Your Feature Here — I can’t name every single different project that might be a cupholder. These are just a couple of examples that I’ve seen repeatedly. And, frankly, one product’s cupholder might be another product’s transmission. The only thing that matters is how much of an effect your proposed change might have on key metrics.

As a business, you should be solving the problems that have the biggest chance of ensuring your survival. Cupholder projects are distractions that take up too much of your time, and it’s up to you to make sure that every project you commit to is going to give you a decent return.

If you want to identify the cupholders, make sure you’re always asking yourself what problem a feature is solving and how important that problem is compared to all the other problems you could be solving. Cupholders solve the problem of where to put your drink. Brakes solve the problem of how to keep you from smashing into a wall.

Of course, if I got to choose, I’d rather you built me a car that drives itself. Then I can use both hands to hold my drink.

About the guest blogger: Laura Klein is a Principal at Users Know, helping you get to know your users and create better products. Her goal is to help lean startups and other small companies improve their connection to their users and design better products, working directly with startups as a member of the team, not only to design a great product, but also to help you learn how to involve your users in the design process. Follow her on Twitter at @lauraklein.